Segment Financial Data (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 18,210	$ 18,365
Operating Income (Loss)	$ 1,807	$ 2,045
Operating Profit Margin	9.90%	11.10%
Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	$ 5,351	$ 4,817
Operating Income (Loss)	$ 439	$ 433
Operating Profit Margin	8.20%	9.00%
Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	$ 18,643	$ 18,749
Operating Income (Loss)	$ 2,265	$ 2,244
Operating Profit Margin	12.10%	12.00%
Otis [Member]
Segment Reporting Information [Line Items]
Revenues	$ 2,966	$ 3,096
Operating Income (Loss)	$ 371	$ 426
Operating Profit Margin	12.50%	13.80%
Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	$ 3,888	$ 4,323
Operating Income (Loss)	$ 363	$ 529
Operating Profit Margin	9.30%	12.20%
Eliminations and other [Member]
Segment Reporting Information [Line Items]
Revenues	$ (433)	$ (384)
Operating Income (Loss)	(343)	(101)
General corporate expenses [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Operating Income (Loss)	(115)	(98)
Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	6,438	6,513
Operating Income (Loss)	$ 1,092	$ 856
Operating Profit Margin	17.00%	13.10%
United States [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	$ 4,300	$ 3,732
United States [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	11,988	11,588
United States [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	890	912
United States [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	2,008	2,214
United States [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	4,790	4,730
Europe [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	106	108
Europe [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,145	3,379
Europe [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	942	955
Europe [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	1,179	1,292
Europe [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	918	1,024
Asia Pacific [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	230	255
Asia Pacific [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,826	2,032
Asia Pacific [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	913	976
Asia Pacific [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	518	612
Asia Pacific [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	165	189
Other [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	715	722
Other [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,684	1,750
Other [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	221	253
Other [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	183	205
Other [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	565	570
Commercial and industrial, non aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	10	23
Commercial and industrial, non aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	6,875	7,456
Commercial and industrial, non aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	2,966	3,096
Commercial and industrial, non aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	3,888	4,323
Commercial and industrial, non aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	11	14
Commercial Aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	3,693	3,375
Commercial Aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	8,279	8,203
Commercial Aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Commercial Aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Commercial Aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	4,586	4,828
Military aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	1,648	1,419
Military aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,489	3,090
Military aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Military aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Military aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	1,841	1,671
Service [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	2,094	1,844
Service [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	5,825	5,525
Service [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	1,843	1,817
Service [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	741	757
Service [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	1,147	1,107
Product [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	3,257	2,973
Product [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	12,818	13,224
Product [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	1,123	1,279
Product [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	3,147	3,566
Product [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	$ 5,291	$ 5,406